BECN flow control
Determines what is done when a backward explicit congestion notification, which is notification to a transmitting device that the network is congested, is received. Checking this value means transmission will be throttled back. Most systems can use the default.
Transmit optimization
Determines how to handle output that arrives so fast that the CIR will be exceeded if the output is forced onto the line immediately. Most systems can use the default (medium), which means data is buffered. Other settings are Conservative, which means drop data in excess of the CIR, and Aggressive, which means force all data onto the line, even if the rate exceeds the CIR.